HE has been one of the most controversial and derided pro-union trolls on Twitter since 2014, but new outrage last week after an online attack on a 17-year-old girl has brought us no nearer knowing the identity of Brian Spanner.

The latest row followed the posting of a video showing Erin Mwembo documenting her journey from No to Yes, which was recorded as part of the online launch of new independence organisation Progress Scotland.

Spanner claimed on Twitter that he had seen evidence that Mwembo had been a Yes supporter in 2017.

Others piled in to criticise the 17-year-old girl.

She was called a “liar” and a “bullshitter”. She was then referred to, via direct messaging, as a“target”.

The message warned her not to “poke a potential hornet’s nest” and that she might be a “target” if the “gloves come off”.

Mwembo and her mother have since locked their Twitter accounts down.

Progress Scotland’s Angus Robertson called it “unacceptable” and said that “trolling is unacceptable full stop”.

He went on: “The targeting of a 17 year-old young woman by aggressive ultra-Unionist trolls reflects very badly on them and their cause. It’s been a positive contrast to see how much support there has been for Erin by fair-minded sensible people across the political spectrum.

“This case should remind all of us who are working towards Scottish independence that how we communicate is as important as what we are saying,” Robertson added of the furore.

“Let’s reach out to the unconvinced. Let’s be welcoming, considerate and respectful.”

The National:

Brian Spanner’s Twitter account sparked abuse 

Spanner later said he had “no interest in a pile on for someone simply asking to participate”. He deleted his original tweet, which he admitted might not have been accurate.

Spanner has been around on Twitter since 2014. The account is anonymous, leading to speculation over the identity – or indentities – of those who post on the account.

Spanner is a consistent critic of the SNP and independence. Highlights of his musings include calling several women c***s.

What elevates the account above the rest is the company he keeps. His followers include JK Rowling, Ruth Davidson and others, he has been defended by the Spectator’s Nick Cohen and commands a significant following.

Mwembo had some significant supporters in the most recent spat. Justice Secretary Humza Yousaf, MP Stuart McDonald and former MP John Nicholson were among those condemning the abuse.

Gail Ross MSP also added her support to Mwembo, with the party saying that trolls like Spanner should be “ashamed” of their mob behaviour.

But the line between shameful and illegal behaviour online is difficult to understand and to manage.

Police can’t prosecute serious online abuse cases unless they are reported to them. They would then have to establish whether or not any criminality had been committed.

This played out in the fallout of the Alex Salmond case online.

There were an infinite number of tweets posted which could potentially have seen the tweeters slapped with a summons for a contempt of court charge.

Any online abuse case has a number of points which must be proved before they can be deemed an offence.

Online offences can include posts or messages which are “grossly offensive or of an indecent obscene or menacing character”.

Messages sent “for the purpose of causing annoyance, inconvenience or needless anxiety to another,” persistently or otherwise – and that are knowingly false – are also examples.

Anyone who is convicted of an online offence could face up to six months in jail or receive a fine.